Cork Institute of Technology
Bachelor of Engineering (Honours) in Structural Engineering – Stage 1
(Bachelor of Engineering in Structural Engineering – Stage 1)
(NFQ – Level 8)
Autumn 2005
Engineering Mechanics
(Time: 3 Hours)
Instructions:
Attempt five questions
This paper contains seven questions
All questions carry equal marks
Take g = 9.81 m/s2
Examiners:
Mr. T. Corcoran
Prof. P. O’ Donoghue
Mr. B. O’ Rourke
Q. 1 The vertical supporting column shown in Figure Q. 1 is securely fixed at point O as
indicated. Cable AB is attached to the top of the column at A and secured to the
ground at point B. The cable is subject to a tensile force T of 12 kN. Calculate the
moment, MZ that T causes about the z-axis passing through the base of the column O.
Q.2 The plane pin-jointed framework shown in Figure Q. 2 is supported by a pin at A and
a roller at E. The framework is subjected to a combination of vertical and horizontal
loads applied at the joints as indicated. Determine the support reactions and hence
determine the forces in the members.
Indicate on a neat sketch of the framework the magnitude (kN) and type (tensile or
compressive) of each member force.
Q. 3 The beam shown in Figure Q. 3 is supported by a pin at A and a roller at D. The beam
is subject to a uniformly distributed load of 12 kN/m vertically from A to B, 8 kN/m
from D to E, along with two additional vertical point loads of 10 kN at C and 15 kN at
E. Determine the reactions at A and D. Draw the shear force and bending moment
diagrams for the beam noting all significant values.
Q. 4 A small concrete retaining wall is supported with formwork as shown in Figure Q. 4
A brace BC is placed for every 1.5m width of wall. Assuming that the joints A, B and
C act as hinged connections, calculate the compression force in each brace BC.
The density of wet concrete may be taken as 2400 kg/m3.
